The long-term goal of this research is to study how CREB binding protein (CBP), a transcriptional coactivator, helps orchestrate mRNA nuclear export. Two proteins, an RNA shuttling protein called TLS (translocated in liposarcoma) and PRMT2 (protein arginine methyltransferase 2), were identified as novel CBP-interacting proteins. This project tests the hypothesis that a PRMT protein methylates TLS and TLS arginine methylation determines its subcellular localization. In vitro methylation assays will test which PRMT family member preferentially methylates TLS. To show whether TLS arginine methylation determines its subcellular localization, cells expressing a green fluorescent protein (GFP) tagged TLS will be treated with arginine methylase inhibitors and fluorescent microscopy will determine how this affects TLS localization. A mutant GFP-TLS protein will also be made, changing the arginines residues to lysines, and fluorescent microscopy used to determine its subcellular localization. Finally, biochemical techniques will be used to identify proteins that preferentially interact with methylated TLS. This work has the potential to link CBP.